Automobile brake



Aug. 27, 1929. J. BUTLER AUTOMOBILE BRAKE Filed June 18, 1928 //VVN70R.

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Patented Aug. 27, 1929.

UNITED STATES PATENT OFFICE.

JAMES BUTLER, F HARRIETSVILLE, ONTARIO, CANADA.

AUTOMOBILE BRAKE.

Application filed June 18, 1928. Serial No. 286,433..

My invention relates to improvements in automobile brakes, and theobject of the inment and construction of parts as hereinafter moreparticularly explained.

Fig. 1 is a face sectional View on line 1 1 Fig. 2.

Fig. 2 is a transverse sectional View through the centreof Fig. 1.

In the drawing like characters of reference indicate corresponding partsin each figure.

1 indicates the brake drum of any usual construction, and 2 the disccarried by the axle and from which the axle arm 3 extends in the usualmanner. The disc 2 is provided with a peripheral recess 3 for a purposewhich will hereinafter appear.

5 and 5 are parallel guides secured to the inner face of the disc andbetween which is slidably mounted a slide plate 6 having a slottedopening 7 through which the axle arm 3 extends. 8 is an arm extendingfrom the plate 6 and provided with an offset portion 9 extending throughthe recess 6 so as to avoid the brake drum 1 as will be clearly seen onreference to Fig. 2.

10 and 11 are the brake shoes mounted to move diametrically of the disc2 between the guides 10 and 10 and 11" and 11.

\Vhon a horizontal movement is imparted to the plate 6 between theguides 5 and 5 the brake shoes 10 and 11 are moved at right angles tothe line of movement of the plate 6, such shoes being moved bodilyparallel to this line of direction by means of the following mechanismwhich "I will now describe.

13 and 14 are links pivotally connected to the shoe 10 at 13 and 14",and 15 and 16 are links pivotally connected at 15 and 16 to the shoe 11.17 and. 18 are bell cranks pivoted at 17" and 18" to the disc 2, and 19and 20 are bell cranks pivoted at 19 and 20 also to the disc 2.

The long arms of the bell crank 17 and 18 are pivoted at 17 and 18 tothe slide plate 6 and the long arms of the bell cranks 1-9 and 20 arepivoted at 19 and 20 to the opposite side of the slide plate 6.

The short arms of the bell cranks 17 and 18 are pivotally connectedat 21and 22 to the inner ends of the links 13 and 14, and

the short arms of the bell cranks 19 and 20 at 23 and 24 to the innerends of the links 15 and 16.

It will thus be seen that when the plate 6 is drawn in the direction ofarrow, the short arms of the bell cranks 17 and 18, 19 and 20 will beswung outward simultaneously carrying the links .13- and 14, 15 and 16in a corresponding direction and each end of the shoes to which they areconnected evenly and parallel to thevertical centre line of the brakeinto contact with the inner periphery of the brake drum, such contactbeing even from end to end of each shoe, and thereby distributing thewear on the shoes so that they will not be worn unequally and therebyquickly lose their usefulness.

It will also be seen by my construction the whole surface of the shoe iscarried into gripping contact with the brake drum so as to therebyprovide, a maximum gripping effect between the shoes and the drum.

What I claim as my invention In an automobile brake, the combinationwith the brake drum and axle disc having a slotted opening at itsperiphery, of a slide plate mounted upon the inner face of the disc .tomove diametrically, means extending through the slotted opening of thedisc for operating the plate, brake slfoes arrangedat opposite points ateach side of the plate, guides between which the brake shoes move, linksconnected to the shoes at each end thereof, a bell crank correspondingto each link pivotally mounted upon the disc, and a pivotal connectionbetween one arm of the bell crank and its corresponding link, and apivotal connection between the other arm of the bell crank and theplate.

I JAMES BUTLER.

